Process of washing nitroglycerine and similar esters



March 14, 1933. sg I 1,901,003

PROCESS OF WASHING NITROGLYCERINE AND SIMILAR ESTERS Filed Jan. 1928 IN V EN TOR.

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Patented Mar. 1 1 .933

MANNHEIBI, GEEMANY rraa staresi airserr crates ARNOLD SCHMID, or VIENNA, AUSTRIA; Hans scmvrrn AND IRMA scHMIn, Aimmrsrnarons or slain ARNOLD scnmrn, nncnasnn, ASSIGNORS r0 KARL sump, or

PROCESS OF WASHING. NITROGLYCEBINE AND SIMILAR ESTERS QApplieation filed January 25, 1928, Serial No. 249,435, and in Germany February 5, 1927. i

The object of the hereindescribed process is to effect the washing of the esters formed during the ni ration of glycerine, glycol and similar alcohols in a continuous opera tion and in a simple reliable manner for the purpose of completely removing the last traces of acid.

A process is known wherein nitroglycerine is freed from the acid dissolved therein by a continuous washing operation but this is only possible by using a'large number of washing vessels.

Nitroglycerine has, for instance, a very gooddissolving capacity for nitric. acid and therefore retains the last traces of the acid I so that even if a soda solution-is used as the washing agent, the washing operation occupiesa great deal of time and a thorough stirring take place. When carrying out the known process liquid eddies are always formed in the washing vessel whereby the portions of the acid nitroglycerine are carried along. before they are deacidified. These portions are again mixed with deacidified nitroglycerine and naturally damage a great part thereof.

The present invention that the acid nitrating product is first emul- 'sified by athorough mixing with the washing agent and then this emulsion is led slow ly on a long path while avoiding whirling motions which might bringthe acid nitrating product in contact with the deacidified product, so that the washing agent has time to dissolve the acid out ofthe finely divided nitrating product and there is alarge space between the place where the acid nitrating product is emulsified with the washing agent and the outlet for the deacidified product. The emulsion must remain on the entire path on which it is moved.

must also be provided for preventing a whirling motion in the direction of the movement of the emulsion, that is to say, mechanical means must be used to prevent resides in the fact Means the unwashed product at the emulsifying place from being carried into the washed emulsion. V g 7 If a vertical cylinder is used for carrying out this process, the acid nitrating product passes with the washing liquid into the lower part of the cylindrical chamber and the emulsification takes place by means of a thorough agitation. This may be effected I by rotating vanes and preferably by the admission of compressed air.) The unobstructemulsion is maintained during its'passagev through the cylinder. 7 r If only a washing agent such as a soda solution is used, a single washingvessel is 'quite sufficient .for obtaining a stable nitrated' product. If however, several washing agents are to be usedbehind one;-another, just as many washing columns must be arranged successively.

The accompanying drawing explains the new process with reference to an example: The vessel '1 is of a cylindrical shape and is divided into the chambers 3 by the perfo This is attained rated plates 2. The acid nitrating product passes through the distributor 4,-the wash chamber where the emulsion mg liquid-through pipe 5 and the compressed air through pipe 6 into thelowest "is formed which is now mixed with air and passes in a frothy condition to the overflow pipe 7 whence it isdischarged in. a small separat-- ing apparatus. The compressed air escapes -i-withthe-formal carbonieacid through thev I I I l l H ,h k 8 Iclaim:

' mwProcess'ofcontinuously;washing-liquidm :estersofnimi'ic'acic'l; which cnmprises e m ul- I I I I I "sifyi-ng the same Withwwashingagent-main -11ai11ing the emulsion in an extended slowly I I I a .flowing bady for some-time, locally'agitah' I I I I ingto maintain the emulsification but avoicL l I I I ingan intermingling of the freshly infirm I i =ducedacidulouszester with tha already'deyfiw I acidified portions; I lntestimonywhereof1afiixmysignaturer I f I I ARNOLD SGHMID. I 

